Learning Modules

People with AMD have central blindness, but peripheral vision is spared. AMD is usually described as 2 forms:1-3 (See Figure below)

  • “Dry” (atrophic) AMD: approximately 80% to 90% of cases are considered the dry form which can slowly progress to late- (geographic) or end-stage disease.
  • “Wet” (neovascular, new vessels) AMD: approximately 10% to 20% of cases are considered the wet form which has a more rapid course that affects vision. Wet AMD is responsible for up to 90% of cases of legal blindness caused by AMD.
Figure: Parts of the eye and effects of macular degeneration4

Although AMD has 2 forms, based on how it develops, it also can be separated into 3 stages based on signs and symptoms that are experienced:1

  • Early (1) and intermediate (2) disease is dry AMD; early-stage AMD usually has no symptoms
  • Advanced disease (3) has progressed to geographic or wet AMD

When visual changes occur, AMD is most likely intermediate to advanced disease. Early detection and referral to an ophthalmologist is important because treatment as soon as possible has more successful outcomes for wet AMD.1,5

The American Academy of Ophthalmology (AAO) recommends the following for comprehensive eye exams in adults with no risk factors for AMD or signs of disease:1,3,6

  • Under age 40 years: every 5 to 10 years
  • Ages 40 to 54 years: every 2 to 4 years
  • Ages 55 to 64 years: every 1 to 3 years
  • Age 65 and older: every 1 to 2 years

You should have a comprehensive medical eye evaluation with an ophthalmologist at age 40 if you have not previously had one.1,3,6

Occasionally people with loss of vision in one eye are not aware of any problems with their vision when sight in the other eye is still good;1,5 therefore, a Snellen exam by an eye care professional may reveal any vision changes that only affect 1 eye. (See Figure below)

Figure: : Snellen chart.

People with symptoms or who have risk factors for AMD should have closer follow up by an eye care professional, and decisions on the number of visits should be made on an individual basis.1,3,6 Persons with significant risk factors should see an ophthalmologist.

People with symptoms of dry AMD complain of a slow blurring of vision in one or both eyes. Activities that require fine visual acuity such as driving or reading are hard to do. They may need to use brighter lights or possibly need to use a magnifying lens for specific tasks.1,7

People with wet AMD may complain of a quick onset of visual alteration or complete loss of central vision in one eye. AMD usually already exists in both eyes, but most frequently only presents in one. Straight lines will appear wavy and distorted, and the edges of windows or doors may appear curved.1,7

People may be given an Amsler grid to self-evaluate on a weekly basis for any changes in vision, such as missing areas of the grid or distorted/wavy lines.1 See the Figure below for an example of a patient self-evaluation of visual changes using an Amsler grid.

Figure: Patient self-evaluation of vision changes using an Amsler grid.1

Everyone with AMD should be educated about healthy lifestyle choices including regular exercise; smoking cessation; wearing protective eyewear in the sun; and a diet that incorporates fruits, vegetables, fish, and nuts.1 Early recognition and coordinated care between primary care providers and vision specialists will lead to timely management, which may decrease the occurrence of permanent blindness due to AMD.1

Two studies sponsored by the National Institutes of Health (NIH), the Age-Related Eye Disease Study 1 and 2 (AREDS 1 and 2), have provided evidence which support that nutritional supplements can reduce the risk of AMD progressing to a more advanced state.1,8 These nutrients include:9

  • Glutathione (GSH)/selenium and vitamin D3 status
  • The family of vitamin E molecules known as tocotrienols/tocopherols
  • Polyphenols
  • The calcium/magnesium ratio
  • Omega-3 fatty acids
  • Zeaxanthin
  • Activities that enhance endothelial nitric oxide production

Based on the results from AREDS 1 and 2, persons with intermediate AMD or advanced AMD, or vision loss in one eye due to AMD, are advised to take a combination of antioxidant supplements and zinc.1

  • Nonsmokers and former smokers can follow the regimen outlined in AREDS 1: vitamin C, vitamin E, beta-carotene, and zinc.
  • AREDS 2 replaced beta-carotene with lutein and zeaxanthin with similar risk reduction; smokers are advised to follow this regimen due to an increased risk of lung cancer with beta-carotene supplementation.

Lutein, zeaxanthin, and beta-carotene all belong to the same family of vitamins, and are abundant in green leafy vegetables.7 Glutathione stimulating hormone (GSH) is also found within the following dietary sources:9

  • GSH: avocados, spinach, asparagus, watermelon, and walnuts; proteins such as chicken, chickpeas, and lentils
  • Cysteine (sulfur bearing): turkey breast, eggs, sockeye salmon, yogurt, wheat germ, whey protein, garlic, onions, soy, red bell peppers, and broccoli
  • Selenium: sardines, Brazil nuts, clams, oysters, turkey breast, and garlic

Nutritional supplements formulated based on these studies are available and their labels may refer to either AREDS or AREDS2.7

First-line therapy for persons with wet AMD is intravitreal injections with vascular endothelial growth factor (VEGF) inhibitors; these agents limit the destructive effects of neovascularization on retinal tissue and can stabilize or may possibly reverse vision loss.1,10 Photodynamic therapy is typically used when there is no response to treatment with VEGF inhibitors. It can be used alone or in combination with VEGF-inhibitor medications. With photodynamic therapy, a dye that is sensitive to light is injected with an activating laser applied through the eye. Tissues with new vessels hold more dye than other vessels which causes damage to these new vessels.1

References

  1. Cunningham J. Recognizing age-related macular degeneration in primary care. JAAPA. 2017;30(3):18-22.
  2. Cheung CM, Wong TY. Is age-related macular degeneration a manifestation of systemic disease? New prospects for early intervention and treatment. J Intern Med. 2014;276(2):140-153.
  3. American Academy of Ophthalmology. Age-Related Macular Degeneration PPP—2019. https://www.aao.org/preferred-practice-pattern/age-related-macular-degeneration-ppp. Accessed April 3, 2020.
  4. American Optometry Association. Macular Degeneration Fact Sheet. https://www.aoa.org/Documents/MacularDegeneration_FactSheet_Web.pdf. Accessed April 7, 2020.
  5. Marra KV, Wagley S, Kuperwaser MC, et al. Care of older adults: role of primary care physicians in the treatment of cataracts and macular degeneration. J Am Geriatr Soc. 2016;64(2):369-377.
  6. American Academy of Ophthalmology. Comprehensive Adult Medical Eye Evaluation—2015. https://www.aao.org/preferred-practice-pattern/comprehensive-adult-medical-eye-evaluation-2015. Accessed April 3, 2020.
  7. NIH/NEI. Age-related Macular Degeneration: What You Should Know. https://www.nei.nih.gov/sites/default/files/health-pdfs/WYSK_AMD_English_Sept2015_PRINT.pdf. Accessed April 6, 2020.
  8. Schmidl D, Garhöfer G, Schmetterer L. Nutritional supplements in age-related macular degeneration. Acta Ophthalmol. 2015; 93(2):105-121.
  9. Richer S, Ulanski L, Natalia A Popenko NA, et al. Age-related macular degeneration beyond the Age-related Eye Disease Study II. Adv Ophthalmol Optometry. 2016;1(1):335-369.
  10. Michalska-Malecka K, Kabiesz A, Nowak M, Spiewak D. Age related macular degeneration—challenge for future: pathogenesis and new perspectives for the treatment. Eur Geriatr Med. 2015;6(1):69-75.
Menu

Clinical Toolkit

The COVID-19 Clinical Toolkit is an online tool that aims to provide clinicians with up-to-date information on the presentation, prognosis, pathophysiology, and treatment strategies for COVID-19. Click on one of the options below to learn more.

This activity is provided by Med Learning Group. This activity is co-provided by Ultimate Medical Academy/CCM.
This activity is supported by educational grants from AbbVie, Astellas, Genentech, Lilly, Merck & Co., Inc., Pfizer and Regeneron Pharmaceuticals, Inc.

Copyright © 2019 | COVID Frontline | All Rights Reserved | Website by Divigner

Updates in the Treatment and Prevention of COVID-19​

Subcutaneous Administration of Casirivimab and Imdevimab Reduced the Risk of Symptomatic COVID-19 by 81% Among Household Contacts

Top-line results from a phase 3 trial showed that the combination of casirivimab and imdevimab reduced the risk of symptomatic infections by 81% among household contacts of SARS-CoV-2 infected individuals. The trial enrolled 1,505 individuals who did not have COVID-19 symptoms or anti-SARS-CoV-2 antibodies, but who lived in the same household as an individual who tested positive for SARS-CoV-2 within the prior 4 days. A single subcutaneous injection of casirivimab and imdevimab provided rapid protection to those with exposure to SARS-CoV-2 at home, with protection against symptomatic infections ranging from 72% in the first week to 93% in subsequent weeks. Individuals who developed symptomatic infections despite casirivimab and imdevimab therapy had a shorter duration of symptoms compared with those who received placebo (1 week vs 3 weeks, respectively). Infected individuals who received therapy also cleared the virus faster. Adverse events (AEs) occurred in 20% of patients receiving casirivimab and imdevimab and 29% of patients receiving placebo. Injection site reactions, all of which were grades 1-2, occurred in 4% of patients in the treatment group and 2% of placebo participants.

Casirivimab and Imdevimab Significantly Reduced Progression to Symptomatic COVID-19 in Recently Infected Asymptomatic Patients

In a phase 3 trial of 204 recently infected asymptomatic COVID-19 patients, subcutaneous administration of casirivimab and imdevimab reduced the overall risk of progressing to symptomatic COVID-19 by 31%, and by 76% after the third day. In addition to reducing the risk of symptomatic infections, the top-line results report that the combination of casirivimab and imdevimab shortened the total number of weeks patients experienced symptoms by 45% and reduced the viral burden by more than 90%. No patients withdrew from the trial due to AEs in either group. Casirivimab and imdevimab are investigational drugs with emergency use authorization for the treatment of individuals with mild-to-moderate COVID-19 who are at high-risk of progressing to severe COVID-19 or hospitalization. Casirivimab and imdevimab (REGEN-COV™) continues to be evaluated in clinical trials in multiple settings for COVID-19, including the open-label RECOVERY trial of hospitalized patients in the UK.

Johnson & Johnson COVID-19 Vaccine Administration Paused

The Centers for Disease Control and Prevention (CDC) and the Federal Drug Administration (FDA) are recommending a pause in the use of the Ad26.COV2.S vaccine developed by Johnson & Johnson (Janssen) as they review data involving 6 reported cases of a rare and severe type of blood clot in individuals after vaccination. The vaccine has been administered to more than 6.8 million individuals in the US. In all 6 reported cases, a type of blood clot called cerebral venous sinus thrombosis (CVST) occurred in combination with low platelet levels (thrombocytopenia). Treatment of CVST differs from other blood clots and administration of heparin may be dangerous in these patients. All 6 cases occurred among women aged 18 to 48 years and symptoms usually occurred 6 to 13 days after vaccination. People who develop severe headache, abdominal pain, leg pain, or shortness of breath within 3 weeks after vaccination should contact their healthcare provider.

References:

Regeneron Press Release. Phase 3 Prevention Trial Showed 81% Reduced Risk of Symptomatic SARS-CoV-2 Infections with Subcutaneous Administration of REGEN-COV™ (Casirivimab and Imdevimab). April 12, 2021. Available at: https://investor.regeneron.com/news-releases/news-release-details/phase-3-prevention-trial-showed-81-reduced-risk-symptomatic-sars

Regeneron Press Release. Phase 3 Treatment Trial in Recently Infected Asymptomatic Patients Showed REGEN-COV™ (Casirivimab and Imdevimab) Significantly Reduced Progression to Symptomatic COVID-19. April 12, 2021. Available at: https://investor.regeneron.com/news-releases/news-release-details/phase-3-treatment-trial-recently-infected-asymptomatic-patients

FDA Statement. Joint CDC and FDA Statement on Johnson & Johnson COVID-19 Vaccine. April 13, 2021. Available at: https://www.fda.gov/news-events/press-announcements/joint-cdc-and-fda-statement-johnson-johnson-covid-19-vaccine